The detailed chemical mechanism of the oxidation of water to O2 is not yet well understood, but with structural information shows_one electron carrier, generally identified as Yz, functions between the oxygen-evolving complex and P680 to function in this region, Yz needs to have a very strong tendency to retain its electrons, this species has been identified as;

TLS Online TPP Program

#Question id: 12996

#Section 2: General Biology

Which of the following is incorrect regarding to α-helix

a) In the α helix, the first four NH groups and last four CO groups will normally lack backbone  hydrogen bonds.

b) the length of an amino acid in α-helix reduced almost 3 times than linear structure.

c) the frequent occurrence of Pro and Gly residues favour α-helix formation.

d) dihedral (ϕ and ψ) angle should be close to -57 and -47.

TLS Online TPP Program

#Question id: 12997

#Section 2: General Biology

Which of the given reason is correct to minimize the repulsion in an α-helix

a) positively charged amino acids are often found near the amino terminus of the helical segment

b) negatively charged amino acids are often found near the amino terminus of the helical segment

c) positively charged amino acids are often found near the C-terminus of the helical segment.

d) negatively charged amino acids are often found near the C-terminus of the helical segment.

TLS Online TPP Program

#Question id: 12998

#Section 2: General Biology

Match with appropriate bonding pattern

TLS Online TPP Program

#Question id: 12999

#Section 2: General Biology

Proline and glycine both disturb the symmetry of α-helix which of the following are true regarding to these two amino acids

a) proline changes the orientation of hetropolymeric α-helix hence proline can be placed only as 1st amino acid residue near to C-terminus 

b) proline changes the orientation of polymeric α-helix hence proline can be placed only as 1st amino acid residue near to N-terminus

c) glycine disrupts the heteropolymeric α-helix by changing the helicity.

d) homopolymer of proline and glycine can form stable helix. 

TLS Online TPP Program

#Question id: 13000

#Section 2: General Biology

Identify the correct statement regarding the structure

TLS Online TPP Program

#Question id: 13001

#Section 2: General Biology

Which of the following is incorrect 

a) antiparallel β sheets are frequently found and they are quite more stable because of more no. hydrogen bond presence and linear H bonding pattern.

b) antiparallel β sheets are frequently found and they are quite more stable because of more no. hydrogen bond presence and having distorted H bonding pattern.

c) parallel β sheets are relatively less stable and mostly found in core of protein.

d) parallel β sheets are relatively more stable and mostly found in core of protein.